Note: Descriptions are shown in the official language in which they were submitted.
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Specification
Pivot motor
The invention relates to a pivot motor according to the preamble
of the first claim and is particularly used in active chassis
for chassis stabilization. DE 197 54 539 C2 describes a pivot
motor that has a cylinder having radial ribs on the inside of
the cylinder; furthermore, a motor shaft having vanes is
disposed in the cylinder, whereby the ribs and the vanes form
working chambers to which a hydraulic pressure can be applied,
causing a rotation of the motor shaft relative to the housing.
DE 36 O1 220 C2 describes a pivot motor activated by pressure
means, in which the pivoting movement is achieved by means of
pairs of threads that engage into one another. In these
solutions, the pivot motor has a high weight and the torque that
can be transferred is relatively low.
It is the task of the invention to develop a pivot motor that
allows the transfer of higher torques, with a light structure
and therefore a low weight.
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This task is accomplished with the characterizing features of
the first claim. Advantageous embodiments are evident from the
dependent claims.
In this connection, the pivot motor consists of a housing that
is closed off with lids on both sides, and has at least one
axially movable first piston in the housing as well as pressure
agent connections, which reach to pressure chambers in front of
and behind the first piston, whereby a rotary shaft can'be put
into rotation by means of an axial movement of the piston.
According to the invention, at least one coupler is disposed
between the first piston and the rotary shaft, which coupler is
mounted in rotary-joint/ball-joint manner at its two ends, and
transfers a rotary moment to the rotary shaft during an axial
movement of the piston.
The coupler has balls at its two ends, which are mounted,
respectively, in a carrier that is attached to a first, piston
and in a carrier that is attached to the rotary shaft, in the
manner of a ball joint. In this connection, the coupler can be
attached to the rotary shaft by way of an intermediate element.
There is a pressure chamber on both sides of the first piston,
in each instance.
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In this connection, a pressure chamber is disposed between the
lid on the piston side and the first piston, to which a pressure
agent line leads, and another pressure chamber is disposed
between the first piston (1.1) and the rotary shaft, to which
another pressure agent line leads.
The rotary shaft is supported on the inside of the lid by way of
a pressure bearing that absorbs axial forces, and the first
piston is guided axially by means of a longitudinal tooth
mechanism. This is preferably done by way of a slide cuff
having a spline bore hub tooth mechanism, which cuff is disposed
on the lid located on the piston side.
In total, a piston with the carrier attached to it and the
couplers mounted there on one end, as well as the carriers
located at the other end of the couplers form an
advancing/pivoting unit.
It is also possible for two or more of these advancing/pivoting
units to be disposed in a housing, whereby preferably, two are
arranged in pairs and as mirror images of one another, in each
instance, so that their pistons point towards one another, but
are separated by a partition and connected with one another so
as to rotate together, by way of a shaft. A pressure chamber
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having a pressure agent feed line is formed between each piston
and the partition and also between the two carriers of an
advancing/pivoting unit, in each instance.
In this way, it is possible to switch any desired number of
advancing/pivoting units one behind the other, in combination
with pressure chambers and pressure agent lines that lie between
them.
In this connection, the advancing/pivoting unit first disposed
on the other end, lying opposite the rotary shaft, is connected
with its carrier, which is attached to the side of the couplers
facing away from the piston, to rotate with the housing or a lid
that terminates the housing on this side. The subsequent
advancing/pivoting units are each mounted in the housing to be
axially and radially movable. By switching pistons, pressure
chambers, and rotary shafts one behind the other, the angle of
rotation and the torque can be adapted to the requirements, in
targeted manner.
In this connection, the carriers are preferably structured in
such a manner that the balls of the couplers are elastically
accommodated.
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The invention will be explained in greater detail in the
following, using exemplary embodiments.
The drawing shows:
Fig. 1: a fundamental representation of a pivot motor in the
initial position,
Fig. 2: the pivot motor according to Fig. 1 after a pivot
movement has been performed;
Fig. 3 a fundamental representation of an advancing/pivoting
unit;
Fig. 4: a fundamental representation of a pivot motor having
two advancing/pivoting units disposed as mirror images
of one another.
Fig. 1 shows a fundamental representation of a pivot motor in
the initial position. A first piston 1.1, which is mounted to
be fixed with regard to rotation and axially displaceable, by
way of a slide cuff 3 having a spline bore hub tooth mechanism,
is disposed in a housing 13. In this connection, the slide cuff
sits on a shoulder 14.1 of the lid 14, which closes off the
housing 13 on this side. A pressure chamber D1 is formed
between first piston 1.1 and lid 14, to which chamber a pressure
agent feed line 2 leads. On the side of the first piston 1.1
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that faces away from the lid 14, the balls 6 of the one end of
four ball-type rods (coupler 7) are mounted to pivot in
spherical segments, by way of a carrier 4, 5. The balls 6 of
the opposite ends of the ball-type rods (coupler 7) are also
mounted to pivot in spherical segments of a second carrier 8, 9.
The balls 6 and the spherical segments of the carriers 4, 5 and
8, 9 thereby form ball joints. A second pressure chamber D2
having a pressure agent feed line 12 is formed between the two
carriers 4, 5 and 8, 9. The carrier 8, 9 is connected with the
rotary shaft 10, which is supported on the other housing lid 15
by way of a pressure bearing 11, by way of an intermediate piece
S. In this connection, the articulated shaft 10 projects
through the housing lid 15. The second carrier 8, 9, the
intermediate piece S, and the rotary shaft 10 are connected with
one another and are mounted to rotate in the housing. The four
ball-type rods (couplers 7) are all inclined at the same angle
and disposed at equal intervals on a common arc. The lids 14
and 15 are tightly welded to the housing 13. The first piston
1.1 and the intermediate piece form a seal towards the inside
wall of the housing 13, and the lid 15 forms a seal towards the
outside diameter of the rotary shaft, by means of seals D.
The method of action is as follows:
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When the cylindrical first piston 1.1 is activated by way of the
first hydraulic connector 2, the first piston 1.1 is displaced,
while being fixed with regard to rotation, by means of the slide
cuff 3 having a spline hub bore tooth mechanism, in the
direction of the rotary shaft 10. The piston force is
transferred to the carrier 8, 9 by way of the double-sided ball-
type rods (couplers 7). As a result of the special slant of the
four couplers 7, an axial force component and one that works in
the circumference direction are produced in the carrier, whereby
the four couplers 7 incline more and more. The circumference
component brings about the desired rotary force on the rotary
shaft by way of the intermediate piece; the amount of this force
is a function of the piston force and the spatial angle of the
ball-type rod, in each instance. The axial component is
compensated by way of the pressure bearing 11.
The opposite direction of rotation until the position of the
first piston 1.1 according to Fig. 2 is reached is brought about
by acting on the pressure chamber D2 by way of the hydraulic
connector 12. In this process, the clearance angle of the
couplers 7 becomes greater and greater. The housing 13, with
the housing lid 14, is designed as a counter-bearing (fixed
bearing) to the rotary shaft 10, so that the torque of the pivot
motor occurs between housing 13 and rotary shaft 10.
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A fundamental representation of the decisive advancing/pivoting
unit V/S is shown in Fig. 3.
This consists essentially of the piston (here, first piston 1.1),
the carrier 4, 5 attached to it, which can, of course, also be
integrated into the piston, the couplers 7 that are mounted in
the carrier 4, 5 at one end, and the second carrier 8, 9 at the
other end of the couplers. Tn this connection, the carriers 4,
5, and 8, 9 are preferably configured in two parts.
It is possible to switch several of these advancing/pivoting
units V/S one behind the other, in combination with
corresponding pressure chambers and pressure feed lines, in
order to adjust the pivot angle of the rotary shaft and the
torque.
A fundamental representation of a pivot motor having two
advancing/pivoting units V/S1, V/S2 disposed as mirror images of
one another is shown in Fig. 4. The first piston 1.1 of the
first advancing/pivoting unit V/S1 and the second piston 1.2 of
the second advancing/pivoting unit V/S2 point towards one
another. A partition 20 is provided between the two
advancing/pivoting units V/S1, V/S2; a shaft 21 projects through
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it, which couples the two pistons 1.1, 1.2 of the
advancing/pivoting units V/S1, V/S2 with one another to rotate
together. The first advancing/pivoting unit V/Sl, with the
carrier 8, 9, is connected with the rotary shaft 10 by way of an
intermediate piece S. The carrier 8, 9 of the second
advancing/pivoting unit V/S2 is firmly connected with the lid
14. The housing 13 is configured in two parts and borders on
the partition 20 on both sides. The first piston 1.1, the
second piston 1.2, and the carrier 8, 9 as well as the
intermediate piece S attached to it, and the rotary shaft 10,
are mounted to rotate in the housing 13. In this connection,
- a pressure chamber D1 having a pressure agent line 2.1 is
formed between the partition 20 and the first piston 1.1,
- a second pressure chamber having a pressure agent line 12.1
is formed between the two carriers 4, 5 and 8, 9 of the
first advancing/pivoting unit V/S1,
- a pressure chamber D3 having a pressure agent line 2.2 is
formed between the partition 20 and the second piston 1.2,
- and a pressure chamber D4 having a pressure feed line 12.2
is formed between the two carriers 4, 5 and 8, 9 of the
second advancing/pivoting unit V/S2.
The method of effect of this pivot motor is as follows:
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When pressure is applied to the pressure chamber D4 by way of
the pressure agent line 12.2, the second piston 1.2 is moved in
the direction towards the rotary shaft 10, and therefore, due to
the coupling with the shaft 21, the first piston 1.1 is also
moved axially in that direction. By means of the couplers 7 of
the second advancing/pivoting unit V/S2, a torque is exerted on
the second piston 1.2 and on the first piston 1.1, which is
transferred to the rotary shaft 10 by way of the couplers 7 of
the first advancing/pivoting unit V/S1, thereby causing the
shaft to rotate. The force component and therefore the torque
can be increased by applying pressure to the pressure chamber D1
by way of the pressure agent line 2.1. In this connection, the
couplers 7 of the second advancing/pivoting unit V/S2 are
"stretched" in the direction towards the longitudinal axis of
the pivot motor. The couplers 7 of the first advancing/pivoting
unit V/S1 remain in their slanted position due to their mirror-
image arrangement, and act as a rigid transfer element between
the first piston 1.1 and the rotary shaft 10.
The opposite direction of rotation of the rotary shaft 10 is
achieved by applying pressure to the pressure chamber D2 by way
of the pressure agent line 12.1 and, if necessary, by applying
pressure to the pressure chamber D3 by way of the pressure agent
line 2.2. In this connection, it is obvious that when pressure
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is applied to one pressure chamber, the pressure in the pressure
chamber that has the opposite effect is reduced. The system can
work hydraulically and pneumatically. In both cases,
corresponding seals D must be provided, which guarantee that the
pivot motor does not leak.
Vibration damping can be achieved by means of coupling the
pressure chambers D2 and D4 by way of the pressure agent lines
12.1, 12.2 and/or by means of coupling the pressure chambers D1
and D3 by way of the pressure agent lines 2.1, 2.2, by way of
the volume flow of the hydraulics of the pneumatics. It is then
possible to use the structural unit also without a rotary shaft,
as a hydraulic or pneumatic vibration damper, or with a
corresponding combination.
